T4 is the type phage of the T4-like phage group (including the other the
T-even phages T2 and T6, and others). The phage is
characterized by an elongated head (85 x 115 nm, T = 13) with whiskers at the neck,
and a contractile tail with lots of
personality, including an elaborate base plate with spikes as well as the prominent
long tail fibers.

Its known hosts includeE. coli.

The electron micrograph shown at left is by
Bob Duda (University of Pittsburgh).